What are you finding slow?

This kinda illustrates what I was talking about re: setting up the N900.

I don't find general usage of the UI slow. I suspect it would seem sluggish if I got used to an S3.

Where I do find the N900 getting slow is when it starts swapping due to the 256MB memory limit. At first, Maemo swaps out stuff you don't need. Then it swaps out stuff you'll need in a minute and then stuff you need in the next second. So it gets progressively slower.

At some point, the N900 actually runs out of swap space and starts rewriting freed blocks. Thus the swap space becomes randomly accessed -- at which point slowness increases exponentially. I would call this mind-bogglingly slow mode.

As mr_pingu said, you can speed all this swapping up as well as expand the swap limit with a microSD card. I've yet to try this as actually sourcing a reasonably priced fast random write card is easier said than done.

You can also defragment the swap without rebooting.